Vapor electric apparatus.



E. E. DARMOIS & M. A. E. LEBLANC.

VAPOR ELECTRIC APPARATUS.

APPLICATION HLED APR.H.19I3.

1,161,801 Patented Nov. 23, 1915.

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WITNESSES ZMz g? ,5 INVENTORS hmdmimw Br 6 mom/E E. E. DARMOIS & M. A. E. LEBLANC.

VAPOR ELECTRIC APPARATUS; APPLICATION FILED APR, 11, I913.

1,161,801 Patented Nov. 23, 1915.

2 SHEETS-SHEET 2.

a INVENTORS UNITED STATES PATENT OFFICE.

EMILE EUGENE DARMOIS AND MAURICE AUGUSTE EUGENE LEIBLANG, 0E PARIS,

FRANCE.

VAPOR ELECTRIC APPARATUS.

Application filed April 11, 1913.

T 0 all whom it may concern Be it known that we, EMILE EUGENE DARMOIS and MAURICE AUGUsTE EUGENE LEBLANC, citizens of the Republic of France, and residents of Paris, France, have invented Certain new and useful Improvements in Vapor Electric Apparatus, of which the following is a specification.

This invention relates to vapor electric apparatus of the kind in which the vapor of mercury or other conducting vaporizable material is arranged to constitute under certain conditions a conducting path for an electric current traversing the apparatus with the result that light or other radiation is emitted from the vapor or the characteristics of the current or circuit are altered in a predetermined manner.

Apparatus of the above description as hitherto employed is essentially continuous or uni-directional in character, that is to say the direction of the flow of current within the vapor is always constant, being either due to an electro-motive force of constant sign impressed on the terminals of the apparatus, as when the latter is operated from a direct current circuit, or, as in the case of vapor rectifiers, to the conversion of an alternating current in the supply circuit to a direct current within the vapor. In the latter case the apparatus is always provided with two or more positive electrodes which are each operative during one-half only of each alternation, the combination of the operative periods of the several positive electrodes causing a flow of current from each electrode in succession through the vapor in a constant direction.

The present invention has for its object to provide an improved vapor apparatus having the same general characteristics as the direct current apparatus above referred to, but which shall be essentially alternating in operation or, in other words, an apparatus in which the flow of current through the vapor due to an impressed alternating electro-motive force, shall occur in both directions so that the apparatus will resemble an ordinary ohmic or inductive resistance as regards permitting the flow of current in either direction.

The improved apparatus will consequently require only two electrodes which are alternately positive and negative and one or both of which may be composed of Specification of Letters Patent.

Patented Nov. 23, 1915.

Serial No. 760,345.

mercury or other vaporizable conducting material necessary for the formation of the this electro-motive force has a minimum or critical value, and unless the impressed electro-motive force is equal to or greater than this value the alternating current operation above described is not obtained. For instance, experiments have shown that at a frequency of alternation of 50 the minimum or critical value is in the neighborhood of 600 n'rtual volts for pure mercury vapor.

A further consideration is the maintenance of the vapor density and temperature of the conducting vapor path at a value which is not lower than a predetermined critical value. o

The invention is illustrated in the accompanying drawings of which Figures 1 to 4 inclusive .are diagrammatic views illustrating various methods of connection of the lamp to a single-phase alternating current supply circuit; Fig. 5 being a diagrammatic view illustrating the connections of a special form of lamp to a polyphase supply circuit and Figs. 6 and 7 are sectional views illustrating details of construction of a preferred form of lamp.

Referring now to the drawings, the lamp 1 comprises a container of glass, quartz, or

other suitable material, of substantially the same form and construction as that of the direct current voltage lamps at present in use, the dimensions of the lamp tube also corresponding approximately to a direct current lamp having the same length of arc and emitting the same amount of light.

In the case of the arrangements shown in Figs. 1 and 2 the lamp is provided with two electrodes 2, 3 and is connected in series with a suitable inductive resistance 4 either directly to the terminals 5, 6 of a supply circuit, as shown in Figs. 1 and 2 or to the secondary Winding 7 of a transformer 8, as shownin Fig. 4, the primary winding 9 of the transformer 8 being connected to the supply circuit.

When the lamp is in operation the drop of potential measured across the terminals may beeffected by increasing the temperature of the vapor column within the lamp container to such'an extent that the vapor density and pressure generated within the container is sufficient to permit the passage of a spark or discharge directly between the electrodes, 2, 3, or the starting operation may be performed by tilting the container of the lamp provided that thetemperature of the electrodes and of the vapor column has been previously increasedto a predetermined minimum value, which can be effected either by heating both the container and the electrodes, or the electrodes only, by a flame or other suitable source of heat such for instance as by a heating resistance surrounding the lamp and operated by direct or alternating current, or by provid-. ing a heating jacket or coil through which hot ases or liquids can be circulated. The heating device may either be attached to or secured to the lamp itself or may be arranged to be removed therefrom as soon as the lamp is started into operation, the control of the heating device being effected either by an electro-magnetic device which is arranged automatically to render the heating apparatus inoperative, or to remove it from the lamp as soon as the lamp has started into operation. The starting operation may also be effected by impressing a momentary high potential upon the terminals of the lamp by means of an inductance.

In the construction illustrated in Fig. 1 the heating resistances for starting the lamp into operation are indicated at 10, 11 as located adjacent to-the electrodes 2, 3 of the lamp. A cut-out switch indicated at 12 is provided controlling the circuit containing the resistances 10, 11; the cut-out switch is being operated by means of the electromagnet 4 which also constitutes the inductance connected in the lamp circuit. In

order further to facilitate thestarting of the lamp a condenser 13 located adjacent to the electrode 2 of the lamp is provided and is connected by means of a conductor 14 to the opposite terminal 6 of the supply circuit. The operation of this form of lamp is as follows 2' The alternating current voltage being impressed upon the terminals 5, 6, the heating resistances 10, 11 are traversed by a corresponding current, the cut-out switch 12 being in its normal or closed position.

As soon as the temperature of the electrode and vapor column of thelamp has reached the critical temperature, an alternating current passes through the lamp between the electrodes 2 and 3 and consequently traverses the electro-magnet 4, which being encrgized opens the cutout switch 12 and interrupts the circuit through the heating resistances 10, 11.

' Referring now to Fig. 2 the lamp 1 is indicated as being of the type in which the lighting tube is entirely filled with mercury or other vaporizable material employed- 'when the lamp is extinguished, the starting operation being arranged to be effected in the manner now Well known 1n connection with direct current lamps by causing a bubs.

ble of vapor to be formed intermediate the electrodes 2, 3. A heater winding 13 surrounding a projection of the lamp tube is an alternating current between these electrodes is superposed upon the rectified current, the value of the alternating current increasing and that of the rectified current decreasing, until finally the latter ceases altogether. In the construction illustrated in Fig. 3 a circuit of each of the main electrodes 2, 3 is in this case provided with a separate inductance 4 and the auxiliary electrode indicated at 14 is connected to the middle point of the secondary winding 7 of the supply transformer 8. The auxiliary electrode 11 is also connected to the electrode 3 of the lamp through a mercury interrupter 15 and the resistances 16, 17, the portion of the container adjacent to the auxiliary electrode 14 being surrounded by a condenser 18 alsoconnected to the electrode 3. In starting the lamp int-o operation a momentary high potential is arranged to be impressed upon the electrodes 3, 14, by a sudden interruption of the circuit effected by means of the mercury interrupter 15, the effect of such interruption being to suddenly break the circuit constituted by the inductance 4, the right half of the secondresistances 16, 17 and rupter 15.

Referring now to Fig. 4, a further modifica'tion is illustrated in which the lamp 1 is arranged to be startedinto operation b tilting the container, the lamp being provided with a pair of auxiliary electrodes, 14c, 19, one, 14, of which is connected to the middle point of the transformer winding 7, the other auxiliary electrode 19 being connected to the electrode 3 of the lamp through a suitable resistance 20. As will be readily understood, the tilting of the container of the lamp causes a momentary connection to be effected between the auxiliary electrodes 14, 19 in the manner now well known in the art.

Referring now to Fig. 5, a special form of lamp 1, having'four electrodes 23, 24, 25, and 26 is illustrated as arranged to be operated from a 2-phase alternating current circuit, the electrodes 23, 25 being connected to the corresponding terminals 27, 28 of one phase of the supply circuit, and the electrodes 24, 26 being connected to the terminals 29, 30 of the other phase. Each phase circuit of the lamp includes a suitable inductance 4 and the operation of this form of lamp will be readily understood without further description.

As above stated, the voltage which it is necessary to impress upon the terminals of the lamp for alternating current operation considerably exceeds that required for the operation of a corresponding lamp by direct current, and it is found in practice that the amount of heat generated at the electrodes is correspondingly increased. In order, therefore, to maintain the electrodes at a suitably low temperature it is of advantage to immerse in the liquid electrodes bodies of suitable metal such for instance as iron, nickel, or other metal having a higher thermal conductivity than mercury or other vaporizable material employed, these bodies serving to conduct heat from the electrodes to the radiating surfaces. In the detail views shown in Figs. 6 and 7 bodies of this character immersed within the electrode are indicated at 21 and the employment of such conducting bodies enables the container of the lamp to be of smaller dimensions than would otherwise be required in order to dissipate the heat generated.

In the arrangement shown in Fig. 6 the body 21 is wholly immersed in the electrode but in certain cases it is found of advantage to constitute the body 21 of tungsten or some other highly refractory metal which is not attacked by the material of which the electrode is composed, and to permit a portion of the body to project beyond the surface of the electrode, Fig. 7 showing a suitable arrangement for this purpose. In order to insure a uniform temperature and consequently uniform vaporization at the two electrodes, it is necessary to so dispose and form the electrodes that the loss of heat by radiation or otherwise is equal for both, so as to prevent any increase in the amount of vaporizable material at either electrode. This may be conveniently effected by so forming the lighting tube of the lamp that the portion of the container in which the two electrodes are located are adjacent to one another, and by providing similar de vices for cooling, such as radiating surfaces, plates or the like, for both. Furthermore, in order to prevent the discharge of vaporizable material from one electrode to the other during operation, or, in other words, to maintain the level of the material the same at both electrodes and to reduce the amount of heat generated, it is of advantage to provide restrictions in the lamptube adjacent to the electrodes, the cross-sectional area of the restrictions in the two cases being the same. Such restrictions are illustrated in Figs. 1 and 6 at 22. as constituted by a thickening of the Wall of the lamp container at a suitable point adjacent to the electrodes.

The introduction of the inductance 4 in the'arrangements above described will evidently cause a corresponding reduction in the power factor of the current traversing the lamp, and in order to reduce this to a minimum it is evidently of advantage to reduce the amount of inductance necessary as much as possible. This can be accomplished by reducing the duration of the interval of time during which the lamp is extinguished at each alternation as the current passing through the lamp falls to zero, and by reducing the potential necessary to effect the re-lighting of the lamp after each such period of extinction. For this purpose any suitable arrangement for increasing the ionization of the vapor within the lighting tube of the lamp may be employed, such for instance as the super-position upon the main are or discharge within the lamp or an auxiliary arc of less intensity and differing in phase to a greater or less extent from the main are. One or more auxiliary electrodes for producing the auxiliary arc may be employed arranged and operating in any well known manner, or additional devices adapted to emit electrons may be located within the lamp tube, such for instance as an incan descent filament, a \Vehnhelt cathode or the like. In order to further facilitate starting of the lamp into operation, one or more conducting bodies may be located within the container of the lamp adjacent to the surface of one of the electrodes so as to facilitate the initial passage of the discharge between the electrodes through the vapor column.

In construction in'which one of the electrodes only is composed of vaporizable material, the arrangements now Well known in connection with vapor apparatus, such as cooling or condensing chambers, can be employed for causing the vaporization to return to that electrode at which the vaporization s effected.

the mercury or othervaporizable material It will be understood that the embodiments of the invention above described may be considerably modified in many respects as for instance by the substitution of other metals, alloys or 'amalgams in place of mercury, or by the introductionof gasesat any suitable pressure other than the vapor of the vaporizable'electrode into the container of the apparatus so as to obtain light radiation having a spectrum difl'erent from that of employed.

From the above remarks .it will be ap-- 1. The method of operating vapor electric apparatus havingmercury electrodes which consists in impressing upon said electrodes alternating current voltage suflicient to operate the lamp and constricting the light path equally at points adjacent to the electrodes.

2. A vapor electric lamp in the .form of a tube having, an electrode near each end thereof, means for impressing an alternating current voltage upon the electrodes and constrictions in" the lamp tube adjacent to each electrode.

A vapor electric lamp in the form of a tube having an electrode near each end thereof, means for impressing an alternating current voltage upon the electrodes and constrictions in the lamp tube adjacent to each electrode and an inductance in the lamp circuit.

Signed by us at Paris, France this fourth day of March, 1913.

EMILEEUGENE DARMOIS. MAURICE AUGUST]! EUGENE LEBLANC- Witnesses:

EDWARD W. BmsEL, LUCIEN MEMMINGER.

Copies of this patent ma y'be obtained for he cents each, by addressing the Commissioner of Patents,

' Washington D. 0. 

